Self-supporting automatic vehicle

ABSTRACT

A self-supporting automatic vehicle capable of performing a self-supporting traveling while controlling the attitude of a body according to the request of a driver who is statically positioned on the body, wherein when the automatic vehicle such as a motorcycle ( 1 ) turns left or right as shown in FIG.  7,  a body inclination sensor successively detects a body inclination amount necessary for coping with the acceleration thereof at that time, a torque according to the detected results is generated by an actuator to tilt the body ( 2 ) a specified amount by a gyro moment generated in a body attitude control means ( 6 ) so as to always align the inclination direction of the body ( 2 ) with the direction of a resultant force acting on the gravity center of the body, and a balance is maintained between a moment based on a centrifugal force, a moment based on a gravity, and the gyro moment from the body attitude control means ( 6 ) at that time, whereby the driver may be statically positioned on the body ( 2 ) without moving a weight.

FIELD OF THE INVENTION

The present invention relates to a self-supporting vehicle whichcontrols an attitude of a vehicle body by a gyro mechanism, and moreparticularly, to a self-supporting vehicle capable of running in aself-supporting manner while controlling an attitude of a vehicle bodyonly by a driver's handlebars operation especially when making a rightturn or a left turn.

BACKGROUND ART

A driver of a bicycle or a two-wheeled vehicle is compelled to maintaina running state by transferring his or her weight by himself or herselfin addition to the operation of handlebars. Especially when driving thetwo-wheeled vehicle which is heavier than the bicycle on a curve at highspeed, the driver is required to swiftly and precisely operate thehandlebars and transfer his own height.

When the driver stops the vehicle to wait at traffic lights at anintersection or the like, or when the running speed is reduced and thecurrent running state can not be maintained only by operating thehandlebars or transferring the weight, the driver is compelled to puthis or her feet on the ground to support the vehicle body in order toprevent the vehicle body from falling or turning over.

DISCLOSURE OF THE INVENTION

Problem that this Invention is to Solve

However, it is excessively strict to require all drivers, especially adriver who drives a two-wheeled vehicle on a curve at high speed, todrive the vehicle while swiftly and appropriately operating handlebarsand transferring the weight because experience is required and such adriving is attended with risk.

It is excessively strict to compel a driver to put his or her feet onthe ground to support the vehicle body in order to prevent the vehiclebody from falling, especially when the vehicle is a two-wheeled heavyvehicle or when the driver is an elderly person or a woman.

It is an object of the present invention to provide a self-supportingvehicle capable of running in a self-supporting manner while controllingan attitude of a vehicle body in accordance with a requirement of adriver who stays still with respect to the vehicle body.

Means for Solving the Problem

To achieve the above object, according to claim 1 of the presentinvention, there is provided a self-supporting vehicle comprising: avehicle body attitude control unit having a rotor turnably supported bya rotor shaft, an inner gimbal for supporting the rotor shaft, and anouter gimbal for supporting the inner gimbal such that the inner gimbalcan turn around an axis which is perpendicular to the rotor shaft; asteering direction detecting sensor that detects a handlebar steeringdirection when making a left or right turn, a vehicle body inclinationamount detecting sensor that detects an inclination amount of a vehiclebody; a first support member for turnably supporting one end of an outergimbal shaft of the outer gimbal on the vehicle body; a second supportmember for turnably supporting the other end of the outer gimbal shaftof the outer gimbal on the vehicle body; an actuator for applying, tothe outer gimbal shaft, a rotation torque corresponding to a detectionsignal of the steering direction detecting sensor and the vehicle bodyinclination amount detecting sensor; and a driving section for supplyinga rotation driving force to the rotor, the driving section including apower source such as an internal combustion engine of a fuel cell.

Claim 2 of the present invention relates to a more concrete structure ofthe vehicle body attitude control unit for such a self-supportingvehicle, and the vehicle body attitude control unit comprises the rotorwhich is turnably supported by the rotor shaft which is in parallel tothe center-of-gravity direction of the vehicle body, the inner gimbalwhich surrounds the rotor and supports opposite ends of the rotor shaftand is provided with a pair of inner gimbal shafts which areperpendicular to the rotor shaft, and the outer gimbal which surroundsthe inner gimbal and turnably supports the inner gimbal through theinner gimbal shafts, and an axis of the outer gimbal is perpendicular tothe rotor shaft and to the inner gimbal shafts and is in parallel to anadvancing direction of the vehicle body.

In this self-supporting vehicle, when making a left turn at a certainspeed, if the driver gently or swiftly turns the handlebars, thesteering direction detecting sensor detects the handlebar steeringdirection and the steering angle, and the actuator applies a torque inthe right rotation direction as viewed from behind the vehicle body tothe outer gimbal shaft by the detection signal. Then, the precession isgenerated in the vehicle body attitude control unit by this torque, anda torque in the left rotation direction, i.e., a gyro moment isgenerated in this shaft. Thus, the vehicle body attitude control unitmaintains the horizontal state which is a state before the driver turnsthe handlebars. On the other hand, this moment supplies a torque in theleft rotation direction to the vehicle body through the first supportmember and the second support member, and the vehicle body inclines tothe left. As the vehicle body inclines, a moment which tries to furtherincline the vehicle body to the left, and a gyro mechanism from thevehicle body attitude control unit 6 which tries to prevent this furtherinclination are applied to the vehicle body and at the same time, amoment which tries to incline the vehicle body to the right is alsoapplied to the vehicle body by a centrifugal force based on acentrifugal acceleration (acceleration in a direction perpendicular tothe advancing direction of the vehicle body).

The vehicle body inclination amount detecting sensor always detects thevehicle body inclination amount corresponding to the acceleration. Theactuator applies a torque having a rotation direction and magnitudecorresponding to the detection signal to the vehicle body attitudecontrol unit. The gyro moment generated in the vehicle body attitudecontrol unit inclines the vehicle body to a vehicle body inclinationamount corresponding to the acceleration so that the inclination angleof the vehicle body is always brought into coincidence with a directionof a resultant force (sum of the gravity and centrifugal force) appliedto the center of gravity of the vehicle body.

That is, the self-supporting vehicle can make a left turn in a state inwhich the inclination direction of the vehicle body always coincideswith the direction of the resultant force applied to the center ofgravity of the vehicle body and while maintaining the balance betweenthe moment based on the current centrifugal force, the moment based onthe gravity and the gyro mechanism generated in the vehicle bodyattitude control unit based on the rotation of the actuator.

Thus, the driver who operates the handlebars can make a left turn onlyby staying still with respect to the vehicle body without transferringhis or her weight.

The driver can also make a right only by staying still with respect tothe vehicle body in the same manner as that when making the left turn.

When the vehicle body tries to incline to the left or right by somereason during the straight running, if a torque in the left rotationdirection or right rotation direction is applied to the vehicle bodyattitude control unit through the first support member and the secondsupport member, the vehicle body attitude control unit generates a gyromechanism in the right rotation direction or the left rotation directionbalancing this torque, i.e., a torque which tries to incline the vehiclebody to the left or right. Thus, when the vehicle body attitude controlunit generates the gyro mechanism, the inclination of the vehicle bodyis prevented and the vehicle body can run straightly while keeping thebalance.

When the attitude of the vehicle body is to be controlled, if aninertial force moment of the rotor around the rotor shaft is defined asJ and the angular speed is defined as ω, the angular speed Ω of theprecession generated in the vehicle body attitude control unit equal toT/Jω (T is a torque applied from outside). When the inertial forcemoment J is great and the angular speed ω is also great, the angularspeed is extremely small. Thus, only a small precession is generated inthe vehicle body attitude control unit with respect to the torqueapplied to the vehicle body attitude control unit from outside. On theother hand, a gyro mechanism balancing the torque T (=J*Δω/Δt) is JωΩ.Thus, if the inertial force moment J and the angular speed ω areincreased, the gyro mechanism is also increased and thus, it is possibleto easily control the attitude of the vehicle body.

According to the self-supporting vehicle according to claim 3 of thepresent invention, when a state in which the vehicle body is inclinedremains due to a deviated load generated in the vehicle body and/or dueto a mechanical loss generated in the vehicle body attitude controlunit, in order to eliminate this inclination state of the vehicle body,a balance weight provided on the centroidal line of the vehicle body ismoved to an appropriate position of the vehicle body. With this, it ispossible to solve a problem that although the vehicle runs straightly,the vehicle body remains inclined and a problem that a difference inspeed or turning radius is generated when making a right turn and a leftturn in the inclination state of the vehicle body.

According to the self-supporting vehicle according to claim 4 of thepresent invention, when the self-supporting vehicle is a two-wheeledvehicle, the vehicle further comprises a rotation number-detectingsensor for detecting the number of rotations of the rotor; acomparing/judging means for comparing and judging the number ofrotations detected by the rotation number-detecting sensor with apredetermined number of rotations with each other; and an auxiliarywheel advancing/retracting unit for retracting auxiliary wheels disposedin the vehicle body into the vehicle body and for advancing theauxiliary wheels out from the vehicle body in accordance with a judgmentresult of the comparing/judging means.

Therefore, when the rotation number-detecting sensor detects the numberof rotations of the rotor and the comparing/judging means compares thedetected number of rotations and the predetermined number of rotationsand judges that the detected number of rotations is smaller than thepredetermined number of rotations, the auxiliary wheeladvancing/retracting unit allows the auxiliary wheels to advance outfrom the vehicle body to prevent the vehicle body from falling.

The predetermined number of rotations which is reference of the judgmentis determined while taking into consideration the magnitude of theinertial force moment and the weight of the vehicle body, but in theactual case, the predetermined number of rotations must be determined byrepeating tests using an actual vehicle while taking the safety andreliability into consideration.

In a normal running state, the auxiliary wheels are retracted into thevehicle body, but even when the vehicle stops, if the number ofrotations of the rotor is equal to or greater than the predeterminednumber of rotations, even if the vehicle body tries to incline to theleft or right by some reason, a gyro mechanism which prevents thisinclination is generated in the vehicle body attitude control unit as inthe straight running state. Therefore, even if the auxiliary wheelsremain retracted into the vehicle body, the vehicle body does not fall.Thus, the driver may stay still with respect to the vehicle body.

Effect of the Invention

According to the self-supporting vehicle of the present invention, thevehicle can run in a self-supporting manner while controlling theattitude of the vehicle body in accordance with a driver's requirementwho stays still with respect to the vehicle body. Therefore, it becomeseasy to drive the vehicle.

According to the self-supporting vehicle of the invention, it ispossible to solve a problem that an inclination state of the vehiclebody remains due to a deviated load caused in the vehicle body and/ordue to mechanical loss generated in the vehicle body attitude controlunit. It is also possible to solve a problem that an inclination stateof the vehicle body remains even during straight running.

According to the self-supporting vehicle of the invention, when theself-supporting vehicle is a two-wheeled vehicle, the vehicle can run ina self-supporting manner in accordance with a requirement of a driverwho stays still with respect to the vehicle body, and the driver is notcompelled to support the vehicle body to prevent the vehicle body fromfalling. Therefore, a burden on the driver during driving is reduced.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic perspective view of a self-supporting two-wheeledvehicle according to an embodiment;

FIG. 2 is a partially sectional plan view of a section of the vehiclewhich controls an attitude of the vehicle body shown in FIG. 1;

FIG. 3 is a partially sectional side view of FIG. 2;

FIG. 4 shows a structure of the self-supporting two-wheeled vehicle forcomparing and judging the number of rotations of a rotor of the vehicle;

FIG. 5 is a sectional view of a vehicle body inclination sensor of theself-supporting two-wheeled vehicle;

FIG. 6 are diagrams for explaining a straight running state and a stopstate of the self-supporting two-wheeled vehicle;

FIG. 7 are diagrams for explaining a light turn or a right turn of theself-supporting two-wheeled vehicle; and

FIG. 8 are diagrams for explaining a motion of another self-supportingtwo-wheeled vehicle of the embodiment.

DESCRIPTION OF REFERENCE NUMERALS

-   1, 40 self-supporting two-wheeled vehicle-   2 vehicle body-   5 driving section-   6 vehicle body attitude control unit-   10 steering angle sensor (steering direction detecting sensor)-   11 vehicle body inclination sensor (vehicle body inclination amount    detecting sensor)-   14 auxiliary wheels advancing/retracting unit-   15 rotor-   15 a rotor shaft-   16 inner gimbal-   16 a, 16 b inner gimbal shaft-   17 outer gimbal-   17 a one end (of outer gimbal shaft)-   17 b other end (of outer gimbal shaft)-   18 magnet sensor (rotation number-detecting sensor)-   20 comparator (comparing/judging means)-   21 first support member-   22 actuator-   23 second support member-   41 balance weight

BEST MODE FOR CARRYING OUT THE INVENTION

One example of a self-supporting vehicle according to an embodiment ofthe present invention will be explained with reference to the drawings.

The present invention will be explained based on a self-supportingtwo-wheeled vehicle. As shown in FIG. 1, a vehicle body 2 of theself-supporting two-wheeled vehicle 1 is supported by a front wheel 3and a rear wheel 4. Provided in the vehicle body 2 are a driving section5 having a power source such as an internal combustion engine or a fuelcell, a vehicle body attitude control sensor 6 disposed at a center ofthe vehicle body 2 and connected to a front portion of the of thedriving section 5, a seat 8 for a driver 7 disposed at the center of thevehicle body 2 and immediately above the vehicle body attitude controlsensor 6, handlebars 9 disposed in front of the driver's seat 8 and usedby the driver 7 for making a left turn or a right turn, a steering anglesensor (steering direction detecting sensor) 10 for detecting a steeringdirection of the handlebars 9, and a vehicle body inclination sensor(vehicle body inclination amount detecting sensor) 11 for detecting aninclination amount of the vehicle body 2.

The driving section 5 is provided with a drive shaft 13 which transmitsa power of the driving section 5 to the rear wheel 4 through a chain 12.The driving section 5 is also provided auxiliary wheeladvancing/retracting unit 14 for retracting a pair of auxiliary wheels14 a into the vehicle body 2 and advancing the wheels 14 a out from thevehicle body 2.

As shown in FIGS. 2 and 3, the vehicle body attitude control unit 6includes a rotor 15 which is turnably supported by a rotor shaft 15 a.The rotor shaft 15 a is in parallel to the center-of-gravity directionof the vehicle body 2. The vehicle body attitude control unit 6 alsoincludes an inner gimbal 16 which surrounds the rotor 15, and whichsupports opposite ends of the rotor shaft 15 a, and which is providedwith a pair of inner gimbal shafts 16 a and 16 b arranged perpendicularto the rotor shaft 15 a. The vehicle body attitude control unit 6 alsoincludes an outer gimbal 17 which surrounds the inner gimbal 16 andturnably supports the inner gimbal 16 through the inner gimbal shafts 16a and 16 b. An axis of the outer gimbal 17 is perpendicular to the rotorshaft 15 a and the inner gimbal shafts 16 a and 16 b, and is in parallelto the advancing direction of the vehicle body 2.

The vehicle body attitude control unit 6 is called a vertical gyrohaving a so-called 2 degrees of freedom. The rotor shaft 15 a isadjusted such that the rotor shaft 15 a is in parallel to the centroidalaxis direction of the vehicle body 2, i.e., such that the rotor shaft 15a is perpendicular to the road surface in a state where the vehicle body2 is not inclined, i.e., where the vehicle body 2 is perpendicular tothe road surface.

The rotor 15 is rotatably supported by the rotor shaft 15 a. The rotor15 is rotated by a battery (not shown) of the driving section 5 as adriving source. The rotor shaft 15 a serving as a stator and the rotor15 serving as a rotor formed outside the rotor shaft 15 a constitute aso-called outer rotor type motor.

The method for rotating the rotor 15 is not limited to theabove-described electrical method, and it may be a mechanical methodusing a belt or chain.

As shown in FIG. 4, a magnet sensor (rotation number-detecting sensor)18 comprising a coil or a magnetic resistance element is disposed in thevicinity of the rotor 15. Magnetic mediums 19 are disposed around theouter periphery of the rotor 15 at equal distances from one another. Themagnet sensor 18 is connected to a comparator (comparing/judging unit)20. Thus, if the magnet sensor 18 detects magnetic flux variation causedwhen the rotor 15 rotates, the rotation number of the rotor 15 isdetected, and the comparator 20 can compare and judge the detectedrotation number with predetermined rotation number. Based on thejudgment result, the auxiliary wheel advancing/retracting unit 14 canallow the auxiliary wheels 14 a to retract into the vehicle body 2 or toadvance out from the vehicle body 2.

The sensor for detecting the rotation number of the rotor 15 is notlimited to the magnetic encoder, and the sensor may be an opticalencoder, a rotary potentiometer, a tachometer generator or the like, ofcourse.

As shown in FIGS. 2 and 3, in the vehicle body attitude control unit 6,one end 17 a of an outer gimbal shaft is turnably supported by a firstsupport member 21 with respect to the vehicle body 2. In thisembodiment, the other end 17 b of the outer gimbal shaft is connected toa rotor of an actuator 22 of the driving section 5, and a stator of theactuator 22 is supported by a second support member 23. Thus, the otherend 17 b of the outer gimbal shaft is turnably supported by the secondsupport member 23 with respect to the vehicle body 2. The first supportmember 21 and the second support member 23 are fixed to the vehicle body2.

The actuator 22 supplies rotation torque based on a control signal fromthe steering angle sensor 10 or the later-described vehicle bodyinclination sensor 11 to the outer gimbal shaft. If the actuator 22 cansupplies the rotation torque to the outer gimbal shaft, the actuator 22may be any of electric actuator, hydraulic actuator and air pressureactuator, of course.

Although the vehicle body attitude control unit 6 is disposedimmediately in front of the driving section 5 in this embodiment, theposition of the vehicle body attitude control unit 6 is not limited tothis, and the unit 6 may be disposed in any place only if handlingcomfort, safety of the vehicle and safety of a driver 7 of the rotor 15which rotates at high speed can be secured. A plurality of vehicle bodyattitude control units 6 may be disposed in series.

As shown in FIG. 5, the vehicle body inclination sensor 11 includes apendulum 25 attached to an upper surface of the case 24 such that thependulum 25 can rock, a coil 26 fixed to a lower portion of the pendulum25, a yoke 27 fixed to a side surface of the case 24, and a magnet 28disposed on the yoke 27 such that the magnet 28 magnetically engageswith the coil 26. The vehicle body inclination sensor 11 also includes adisplacement detector 29 having magnetic elements which are opposed to alowermost end of the pendulum 25, a servo amplifier 30 having an inputside connected to the displacement detector 29 and an output sideconnected to the coil 26, and a reading resistor 31 for taking outcurrent flowing through the coil 26 as output voltage.

In the vehicle body inclination sensor 11, when making a left or rightturn, if acceleration in a direction A or B is applied to the vehiclebody 2, the pendulum 25 tries to move in the opposite direction by aninertial force. This movement is detected by the displacement detector29, current is allowed to flow through the coil 26 by a detection signalto return the pendulum 25 to its original position, thereby bringingthis movement and a force of the acceleration into balance, and thecurrent at that time is taken out as the output voltage through thereading resistor 31. This taken out output voltage is proportional tothe magnitude of the acceleration, and the inclination amount of thependulum 25 (=inclination amount of the vehicle body 2) is alsoproportional to the magnitude of the acceleration. Therefore, it ispossible, by this output voltage, to detect the vehicle body inclinationamount which corresponds to acceleration for inclining the vehicle body2.

Although the rocking type acceleration sensor is used as the vehiclebody inclination sensor 11 in this embodiment, the sensor 11 may be astrain gage using a silicon semiconductor of course.

The steering angle sensor 10 may be an electromagnetic or opticalptoelectric sensor, or a semiconductor sensor using a Hall element, onlyif the sensor can detect the steering direction and the steering angleof the handlebars 9 which are operated when the driver 7 makes a left orright turn.

The mechanism of the auxiliary wheel advancing/retracting unit 14 is notespecially limited only if the unit 14 can retract the pair of auxiliarywheels 14 a into the vehicle body 2 and advance the wheels out from thevehicle body 2. In this embodiment, as shown in FIG. 1, a caster 14 chaving the auxiliary wheel 14 a is connected to an arm 14 b extendingfrom the driving section 5, and the auxiliary wheel 14 a is retractedinto the vehicle body 2 or advanced out from the vehicle body 2 byrotating the arm 14 b.

Next, operation of the self-supporting two-wheeled vehicle 1 having theabove-described structure will be explained with reference to FIGS. 6and 7. The self-supporting two-wheeled vehicle 1 has the same functionand performance as those of the conventional two-wheeled vehicle and canrun in the same manner. Here, only straight running and left or rightturning of the vehicle 1 will be explained.

First, the operation or action from the start to the stop of thetwo-wheeled vehicle 1 through the straight running will be explained.

When the vehicle stops, as shown in FIG. 6(A), the auxiliary wheels 14 aadvance out from the vehicle body 2 and come into contact with the roadsurface to prevent the vehicle body 2 from falling.

Then, the driver 7 seats on the driver's seat 8 and grasps thehandlebars 9, and starts the driving section 5 by a starter or the like,and the rotor 15 starts rotating. The magnet sensor 18 detects therotation number of the rotor 15. The comparator 20 compares thisrotation number with the predetermined rotation number and if thecomparator 20 judges that the detected rotation number is greater thanthe predetermined rotation number, the auxiliary wheeladvancing/retracting unit 14 retracts the auxiliary wheels 14 a into thevehicle body 2, and the two-wheeled vehicle 1 is brought into a stateshown in FIG. 6(B) while maintaining a so-called idling state.

Even in this idling state, if the rotation number of the rotor 15 isgreater than the predetermined rotation number, the vehicle body 2 triesto incline to the left or right, and a torque (external force) in a leftrotating direction or in a right rotation direction is applied to thevehicle body attitude control unit 6 through the first support member 21and the second support member 23. If this torque is applied, a gyromoment in the right rotation direction or the left rotation directionbalancing this torque, i.e., a torque inclining the vehicle body 2 tothe left or right is generated. Therefore, the vehicle body 2 isprevented from being inclined, and even if the auxiliary wheels 14 aremain retracted in the vehicle body 2, the vehicle body 2 does notfall. What the driver 7 must to do is only to seat on the driver's seat8 and grasp the handlebars 9.

The vehicle body inclination sensor 11 always detects the vehicle bodyinclination amount. If a balance between a moment based on the externalforce and a gyro moment from the vehicle body attitude control unit 6(also including a moment based on the gravity applied to the vehiclebody 2) is lost, the vehicle body inclination sensor 11 provides theactuator 22 with rotation instructions in a predetermined direction,increases or reduces the gyro moment generated in the vehicle bodyattitude control unit 6 so that the vehicle body 2 is not inclined tothe left nor right and the perpendicular or vertical state of thevehicle body 2 with respect the road surface is maintained.

From such a state, the driver 7 can drive the vehicle straightly byoperating a clutch or the like in the same manner as that of theconventional two-wheeled vehicle.

Even if the vehicle body 2 inclines to left or right during the straightrunning, since the gyro moment which prevents the vehicle body 2 frombeing inclined to the left or right is generated in the vehicle bodyattitude control unit 6 as in the same manner as described above, thedriver 7 needs not transfer his or her weight and may stay still to thevehicle body 2. In such a case also, the vehicle body inclination sensor11 always detects the vehicle body inclination amount, and if thebalance between the moments is lost, the vehicle body inclination sensor11 increases or reduces the gyro moment to maintain the vehicle body 2in the perpendicular state with respect to the road surface.

Next, the left and right turning operations of the two-wheeled vehicle 1will be explained with reference to FIGS. 7.

FIG. 7(A) shows the vehicle body when making a left turn as viewed frombehind, and FIG. 7(B) shows the vehicle body when making a right turn asviewed from behind.

When the two-wheeled vehicle 1 makes a left turn, if the driver 7 gentlyor abruptly turns the handlebars 9 to the left, the steering anglesensor 10 detects the steering direction and the steering angle of thehandlebars 9, the actuator 22 applies a torque in the right rotationdirection as viewed from behind the vehicle body 2 to the one end 17 aand the other end 17 b of the outer gimbal shaft by the detectionsignal. Then, precession is generated in the vehicle body attitudecontrol unit 6 by this torque, a torque in the left rotation direction,i.e., the gyro moment is generated in the shaft. Therefore, the vehiclebody attitude control unit 6 maintains a horizontal state which is astate before turning the handlebars 9. On the other hand, by thismoment, a torque in the left rotation direction is applied to thevehicle body 2 through the first support member 21 and the secondsupport member 23, and the vehicle body 2 is inclined to the left. Asthe vehicle body 2 inclines in this manner, a moment which tries tofurther incline the vehicle body 2 to the left by the gravity, and agyro moment from the vehicle body attitude control unit 6 which tries toprevent the further inclination are supplied to the vehicle body 2, anda moment which tries to incline the vehicle body to the right by acentrifugal force based on the centrifugal acceleration, i.e., a momentwhich tries to prevent the inclination of the vehicle body 2 is appliedto the vehicle body 2.

The vehicle body inclination sensor 11 always detects the vehicle bodyinclination amount which corresponds to the acceleration, and theactuator 22 generates a torque having a rotation direction and magnitudecorresponding to the detection signal. When the vehicle body inclinationamount corresponding to the current acceleration is not sufficient forexample, if the vehicle body inclination sensor 11 provides the actuator22 with predetermined rotation instructions, a torque in the leftrotation direction is applied to the vehicle body 2 based on the gyromoment generated in the vehicle body attitude control unit 6, and thevehicle body 2 inclines by a vehicle body inclination amountcorresponding to this acceleration. The two-wheeled vehicle 1 makes aleft turn while maintaining the balance between a moment based on thecentrifugal force of at that time, a moment based on the gravity and agyro moment from the vehicle body attitude control unit 6 (FIG. 7(A)).

If the driver 7 further turns the handlebars 9 to the left, the steeringangle sensor 10 detects this operation, a gyro moment corresponding tothe increased torque from the actuator 22 is generated in the vehiclebody attitude control unit 6, and the vehicle body 2 further inclines tothe left based on this moment. If the vehicle body inclination amountcorresponding to the acceleration of that time is excessively great, agyro moment corresponding to a reduced torque from the actuator 22 isgenerated, and the vehicle body 2 rotates to the right so as tocorrespond to the current acceleration based on this moment, therebycorrecting the vehicle body inclination amount.

In the two-wheeled vehicle 1, the vehicle body inclination sensor 11always detects the vehicle body inclination amount corresponding to thecurrent acceleration, and a rotation torque corresponding to thedetection result is generated from the actuator 22, the vehicle body 2is inclined by a predetermined amount by the gyro moment generated inthe vehicle body attitude control unit 6, the inclination direction ofthe vehicle body 2 is brought into coincidence with a direction of aresultant force applied to the center of gravity of the vehicle body,the vehicle can make a left turn while maintaining the balance between amoment based on the centrifugal force of at that time, a moment based onthe gravity and a gyro moment from the vehicle body attitude controlunit 6. Thus, the driver 7 may only stay still in the vehicle body 2without transferring his or her weight.

When the vehicle makes a right turn, the vehicle body attitude iscontrolled in the same manner as that required when making the leftturn. Thus, the vehicle body 2 is inclined to the right as viewed frombehind (FIG. 7(B)), and the driver 7 may only stay still in the vehiclebody 2 without transferring his or her weight.

Here, the resultant force applied to the center of gravity of thevehicle body is a resultant force of the centrifugal force caused by thecentrifugal acceleration and the gravity applied to the center ofgravity of the vehicle body.

When the vehicle body 2 runs straightly for example, even if the vehiclebody 2 inclines to the left or the right, the vehicle body attitudecontrol unit 6 generates the gyro moment which prevents this. Thus, thevehicle body 2 can run straightly while maintaining the perpendicularstate with respect to the road surface as described above. However, whena deviated load W keeps applying to the vehicle body 2 as shown in FIG.8(A), there is caused a problem that even if the vehicle runsstraightly, the vehicle remains inclined. Thus, it is necessary to solvethis problem. One example of this solving method of this problem will beexplained with reference to FIGS. 8(A) to (C) using a self-supportingtwo-wheeled vehicle 40 having a balance weight 41. FIGS. 8 show thevehicle body as viewed from behind.

When the vehicle body 2 runs straightly, if the deviated load W isapplied to a left end of the vehicle body 2 and the vehicle body 2inclines to the left, a gyro moment in the right rotation directionbalancing this torque, i.e., a torque which tries to incline the vehiclebody 2 to the right is generated, and unbalance generated by a momentbased on the deviated load W (also including a moment based on thegravity applied to the vehicle body 2) is canceled. At that time, sincethe unbalance is canceled, the vehicle body 2 inclines to the right asshown in FIG. 8(B). However, it is unnatural to run straightly in thisrightward inclining state. Thus, when the inclination amount remains inthe vehicle body 2, i.e., when the vehicle body 2 remains inclined tothe right in this embodiment, in order to bring the vehicle body 2perpendicular to the road surface, the balance weight 41 provided on thecentroidal line of the vehicle body 2 is moved to a right end of thevehicle body 2 by a ball screw mechanism 42 for example as shown in FIG.8(C), a torque which tries to incline the vehicle body 2 to the left isgenerated in the vehicle body attitude control unit 6, thereby allowingthe vehicle body 2 to maintain the perpendicular state to the roadsurface. With this, it is possible to solve the problem that althoughthe vehicle runs straightly, the vehicle body 2 remains inclined. Themechanism for moving the balance weight 41 is not limited to the ballscrew mechanism 42 as in this embodiment, and the balance weight 41 maybe moved like a pendulum.

The balance weight 41 before it moves is located on the centroidal lineof the vehicle body 2 in the state where the vehicle body 2 isperpendicular to the road surface as shown in FIGS. 8(A) and (B).

When the vehicle body 2 runs straightly, even if the vehicle body 2inclines to the left or the right, the vehicle body attitude controlunit 6 generates the gyro moment which prevents this. Thus, the vehiclebody 2 can run straightly while maintaining the perpendicular state withrespect to the road surface, but due to a mechanical loss generated inthe vehicle body attitude control unit 6, there is cause, in some cases,a problem that the inclination amount remains in the vehicle body 2 orthe inclination amount is gradually increased. Thus, such a problem mustbe solved. As one method for solving the problem, the balance weight 41may be moved by the ball screw mechanism 42.

That is, if the vehicle body 2 tries to incline to the left or the rightand a torque (external force) in the left rotation direction or theright rotation direction is applied to the vehicle body attitude controlunit 6, a gyro moment in the right rotation direction or the leftrotation direction balancing this torque, i.e., a torque for incliningthe vehicle body 2 to the right or left is generated in the vehicle bodyattitude control unit 6. The vehicle body inclination sensor 11 alwaysdetects the vehicle body inclination amount, and when the balancebetween these torques is lost, since the gyro moment generated in thevehicle body attitude control unit 6 is increased or reduced, thevehicle body 2 is maintained in the perpendicular state with respect tothe road surface. However, when the inclination of the vehicle body isnot corrected and the inclination amount remains due to the mechanicalloss of the vehicle body attitude control unit 6 or the inclinationamount is gradually increased in one direction, the vehicle body 2 isinclined as shown in FIG. 8(B) for example. It is unnatural for thevehicle to run straightly in this state. Thus, in order to bring thevehicle body 2 perpendicular to the road surface, the balance weight 41provided on the centroidal line of the vehicle body 2 is moved to anappropriate position of the vehicle body 2 by the ball screw mechanism42, thereby maintaining the vehicle body 2 in the perpendicular statewith respect to the road surface. With this, it is possible to solve theproblem that although the vehicle runs straightly, the vehicle body 2remains inclined.

As described above, if a rotation torque T is applied to the vehiclebody attitude control unit 6 by the actuator 22, the vehicle bodyattitude control unit 6 generates a gyro moment balancing this rotationtorque T. In this case, the angular speed Ω of the precession generatedin the vehicle body attitude control unit 6 can be found by an equationof Ω=T/Jω (wherein J is an inertial force moment of the rotor 15 aroundthe rotor shaft 15 a, and ω is the angular speed), if the inertial forceJ is great and the angular speed ω is great, the angular speed Ω isextremely small. In such a case, the vehicle body attitude control unit6 is not inclined almost at all, and the vehicle body can maintain itsperpendicular state with respect to the road surface. Since the gyromoment can be obtained by the JωΩ, the gyro moment is extremely great,and it is possible to easily control the attitude of the vehicle body 2.

The vehicle body of the conventional two-wheeled vehicle is not providedwith a side member of roof for protecting the driver from wind and rain.If the two-wheeled vehicle 1 is provided with a side member 2 a and aroof 2 b as shown in FIG. 1, habitability for the driver 7 is enhanced.Two people can ride on the two-wheeled vehicle 1 like the conventionaltwo-wheeled vehicle.

Although the self-supporting vehicle has been explained based on theself-supporting two-wheeled vehicle in this embodiment, the vehicle maybe a three-wheeler having two rear wheels.

INDUSTRIAL APPLICABILITY

The self-supporting vehicle can run in the self-supporting manner whilecontrolling the attitude of the vehicle body in accordance withrequirement of a driver who stays still with respect to the vehiclebody. Therefore, any one can drive the vehicle without depending upon adriving technique of the driver. When the self-supporting vehicle is atwo-wheeled vehicle having two wheels, the vehicle can run in theself-supporting manner and in addition, the driver is not compelled tosupport the vehicle body for preventing the vehicle body from falling.Thus, a burden on the driver at the time of driving of the vehicle isreduced, and this vehicle is preferable especially when the driver is anelderly person, a woman or a disabled person.

1. A self-supporting vehicle comprising: a vehicle body attitude controlunit having a rotor turnably supported by a rotor shaft, an inner gimbalfor supporting the rotor shaft, and an outer gimbal for supporting theinner gimbal such that the inner gimbal can turn around an axis which isperpendicular to the rotor shaft; a steering direction detecting sensorthat detects a handlebar steering direction when making a left or rightturn, a vehicle body inclination amount detecting sensor that detects aninclination amount of a vehicle body; a first support member forturnably supporting one end of an outer gimbal shaft of the outer gimbalon the vehicle body; a second support member for turnably supporting theother end of the outer gimbal shaft of the outer gimbal on the vehiclebody; an actuator for applying, to the outer gimbal shaft, a rotationtorque corresponding to a detection signal of the steering directiondetecting sensor and the vehicle body inclination amount detectingsensor; and a driving section for supplying a rotation driving force tothe rotor.
 2. The self-supporting vehicle according to claim 1, whereinthe vehicle body attitude control unit comprises the rotor which isturnably supported by the rotor shaft which is in parallel to thecenter-of-gravity direction of the vehicle body, the inner gimbal whichsurrounds the rotor and supports opposite ends of the rotor shaft and isprovided with a pair of inner gimbal shafts which are perpendicular tothe rotor shaft, and the outer gimbal which surrounds the inner gimbaland turnably supports the inner gimbal through the inner gimbal shafts,and an axis of the outer gimbal is perpendicular to the rotor shaft andto the inner gimbal shafts and is in parallel to an advancing directionof the vehicle body.
 3. The self-supporting vehicle according to claim1, wherein when a state in which the vehicle body is inclined remainsdue to a deviated load generated in the vehicle body and/or due to amechanical loss generated in the vehicle body attitude control unit, inorder to eliminate this inclination state of the vehicle body, a balanceweight provided on the centroidal line of the vehicle body is moved toan appropriate position of the vehicle body.
 4. The self-supportingvehicle according to claim 1, further comprising: a rotationnumber-detecting sensor that detects the number of rotations of therotor; a comparing/judging means for comparing and judging the number ofrotations detected by the rotation number-detecting sensor with apredetermined number of rotations with each other; and an auxiliarywheel advancing/retracting unit for retracting auxiliary wheels disposedin the vehicle body into the vehicle body and for advancing theauxiliary wheels out from the vehicle body in accordance with a judgmentresult of the comparing/judging means.
 5. The self-supporting vehicleaccording to claim 2, wherein when a state in which the vehicle body isinclined remains due to a deviated load generated in the vehicle bodyand/or due to a mechanical loss generated in the vehicle body attitudecontrol unit, in order to eliminate this inclination state of thevehicle body, a balance weight provided on the centroidal line of thevehicle body is moved to an appropriate position of the vehicle body. 6.The self-supporting vehicle according to claim 2, further comprising: arotation number-detecting sensor that detects the number of rotations ofthe rotor; a comparing/judging means for comparing and judging thenumber of rotations detected by the rotation number-detecting sensorwith a predetermined number of rotations with each other; and anauxiliary wheel advancing/retracting unit for retracting auxiliarywheels disposed in the vehicle body into the vehicle body and foradvancing the auxiliary wheels out from the vehicle body in accordancewith a judgment result of the comparing/judging means.
 7. Theself-supporting vehicle according to claim 3, further comprising: arotation number-detecting sensor that detects the number of rotations ofthe rotor; a comparing/judging means for comparing and judging thenumber of rotations detected by the rotation number-detecting sensorwith a predetermined number of rotations with each other; and anauxiliary wheel advancing/retracting unit for retracting auxiliarywheels disposed in the vehicle body into the vehicle body and foradvancing the auxiliary wheels out from the vehicle body in accordancewith a judgment result of the comparing/judging means.
 8. Theself-supporting vehicle according to claim 5, further comprising: arotation number-detecting sensor that detects the number of rotations ofthe rotor; a comparing/judging means for comparing and judging thenumber of rotations detected by the rotation number-detecting sensorwith a predetermined number of rotations with each other; and anauxiliary wheel advancing/retracting unit for retracting auxiliarywheels disposed in the vehicle body into the vehicle body and foradvancing the auxiliary wheels out from the vehicle body in accordancewith a judgment result of the comparing/judging means.